鄱阳湖流域洪峰流量和枯水流量变化趋势分析

Trend analysis of flood peak/dry season flowrate in Poyang Lake Basin

利用鄱阳湖流域40多年来的实测流量数据,分析了该流域年最大流量、高于阈值的洪峰流量和枯水流量的变化趋势。分析表明,鄱阳湖流域洪峰流量变化的区域差异较大:多数地区趋势变化不明显,修水上游和抚河上游有增大的趋势,饶河流域是趋势变化最明显的地区——年最大流量、高于阈值的洪峰流量的强度与频率都呈现增大的趋势,这与降水量变化的空间分布基本一致;与洪峰流量变化趋势不同,40多年来,整个鄱阳湖流域枯水流量呈现显著上升趋势。这种趋势的变化在很大程度上是该流域气候变化及其对水循环影响的反映,同时也为研究人类活动对径流的影响提供有意义的参考。

By use of measured flowrate data of Poyang lake Basin for more than 40 years, the change trend of annual maximum flowrate （AM） , peak-over-threshold flowrate （POT） and dry season flowrate are analyzed. The analyses reveal that the flood flowrate of the five subbasins is much different from each other. The change is not significant in most area, while that in Xiushui River and Fuhe River basins has an upward trends. Raohe Rever basin has the most significant positive change, of which the AM and POT （ magnitude and frequency） flowrate both dominate increasing trends. That has a good agreement with the spatial distribution of the precipitation. And as for the dry season flowrate, the much significant upward trend in most part of the Poyang Lake Basin can be found. The trend shows the potential infuence of climate change on the hydrological cycle over Poyang Lake Basin. And it can give a meaningful reference to the study on effects of anthropogenic activities on the river flowrate.